confab vs gab

confab and gab both are nouns.

Word	Noun	Adjective	Verb	Adverb
confab	Yes	No	Yes	No
gab	Yes	No	Yes	No

As nouns, gab is a hyponym of confab; that is, gab is a word with a more specific, narrower meaning than confab:

confab (noun)	gab (noun)
an informal conversation	light informal conversation for social occasions

confab (verb)	gab (verb)
talk socially without exchanging too much information	talk profusely
have a conference in order to talk something over